$mysqli->fetch_object cannot get a result to iterate through - PHP - Mysql - php

Question

I have the current code:
Database::connect();
?>
<table>
<thead>
<tr>
<th>ID</th>
<th>Title</th>
</tr>
</thead>
<tbody>
<?php
$query = "SELECT * FROM app";
$dbr = Database::query( $query );
while( $row = Database::$mysqli->fetch_object( $dbr->result ) ){
?>
<tr>
<td><?php echo $row->id; ?></td>
<td><?php echo $row->title; ?></td>
</tr>
<?php
}
?>
</tbody>
</table>
<?php
Database::close();
?>
and here is the Database and DatabaseQuery classes
class DatabaseQuery{
public $result;
public $mysql_num_rows;
}
class Database{
public static $mysqli;
private static $db_name = '';
private static $username = '';
private static $password = '';
private static $host = 'localhost';
private static $prefix = '';
public static function connect(){
self::$mysqli = new mysqli( self::$host, self::$username, self::$password, self::$db_name );
if (self::$mysqli->connect_error) {
die('Connect Error (' . self::$mysqli->connect_errno . ') '
. self::$mysqli->connect_error);
}
}
public static function query( &$query ){
$query = self::$mysqli->real_escape_string( $query );
if ($stmt = self::$mysqli->prepare($query)) {
$stmt->execute();
$stmt->store_result();
$DatabaseQuery = new DatabaseQuery();
$DatabaseQuery->result = $stmt;
$DatabaseQuery->mysql_num_rows = $stmt->num_rows();
$stmt->close();
return $DatabaseQuery;
}
}
public static function close(){
self::$mysqli->close();
}
}
I'm getting an error in my calling code: Fatal error: Call to undefined method mysqli::fetch_object()
Any ideas?

Answer 1

Replace your following line:
while( $row = Database::$mysqli->fetch_object( $dbr->result ) ){
for this one:
while( $row = $dbr->fetch_object( $dbr->result ) ){
Because fetch_object() is a method of mysqli_result object, and not of the general mysqli object.

Answer 2

I think this is your problem, but I would suggest looking into PDO's a very simple way of accessing databases and working with them.
<?php
$query = "SELECT * FROM app";
$dbr = Database::query( $query );
//Change this here since your method is query and not $mysqli
while( $row = Database::$dbr->fetch_object( $dbr->result ) ){
?>
<tr>
<td><?php echo $row->id; ?></td>
<td><?php echo $row->title; ?></td>
</tr>
<?php
}
?>
If your dont mind I would say u are complicating your class a lot. If u have a reason then ok if not u could do it like this.
class Database{
private static $mysqli;
private static $db_name = '';
private static $username = '';
private static $password = '';
private static $host = 'localhost';
private static $prefix = '';
public function __construct(){
self::$mysqli = new mysqli( self::$host, self::$username, self::$password, self::$db_name );
if (self::$mysqli->connect_error) {
die('Connect Error (' . self::$mysqli->connect_errno . ') '
. self::$mysqli->connect_error);
}
}
public function query( $query ){
$query = self::$mysqli->real_escape_string( $query );
if ($query = self::$mysqli->prepare($query)) {
$query->execute();
$query->store_result();
$stmt = $query->result;
//$query->mysql_num_rows = $stmt->num_rows();
$query->close();
return $stmt;
}
}
}
The file that uses the class
//Include the file unless u have a autoloader
<tr>
<?php
$query = "SELECT * FROM app";
$dbr = new Database();
//Change this here since your method is query and not $mysqli
while( $row = $dbr->query($query)->fetch_object() ){
echo '<td>'. $row['IDcolumnName'] . '</td>' ;
echo '<td>'. $row['TitlecolumnName'] . '</td>' ;
}
?>
</tr>

Answer 3

Your logic is broken:
$query = self::$mysqli->real_escape_string( $query );
You do not escape the entire query. You escape data you're inserting into a query, e.g. if you had somethign like
SELECT id, name, ... WHERE firstname = '$searchterm'
you'd escape the value in $searchterm. Escaping the entire query turns it into
SELECT id, name, ... WHERE firstname = \'$searchterm\'
and you end up with syntax errors, because you no longer have quotes around $searchterm, you have a couple ignored characters as part of a bare string.
Then there's:
$stmt->store_result();
store_result() returns a statement handle you can use to fetch results from later. You're not capturing that handle, so your DB result is simply thrown away, even if the query had executed properly.